Adjustable die-stock.



. KOEHLBR.

'AIJJ BLE DIE STOCK.

FFIC.

FREDERICK G. KOEI-ILER, OF WARREN, OI-IIO, ASSIGNOR T0 TEE BORDEN COMPANY, OF WARREN, OI'IIO, A CORPORATION OF OI-IIO.

ADJ'USTABLE DIE-STOCK.

T0 all whom lt mag concern:

Be it known that I, FREDERICK G. Konn- LER, 01": V ar1en, in the county of Trumbull und State of Ohio, have invented certain new und useful Improvements in Adjustable DieStocks; und I do hereby dechue the following t0 be a fu1l, c1eal, und exact description 01"? the invention, such as Will enable others skilled in the art t0 which it appertains to 1nake und use the same.

In tlmt dass 0f pipe threading tools wherein one 0r more set-s 0f chasers nmy be adjusted t0 thread pipes 0f different sizes it is customary t0 e1nploy locking means f01 frictionally holding the chaser adjusting plate in different positions. Owing to the tendency 013 the chasers 130 turn such plates axially by the outward pressure 0f the pipe ngainst the chasers during the cutting operation it has heretofore been diflicultto so lock the chaser adjusting plates as t0 guard absolutely against slipping.

The object of 1ny invention is to provide extremely simple and yet highly efficient means f01 preventing slipping of the chaser ndjusting plate after it is locked in position.

The invention Will be hereinafter fully set forth and particularly pointed 0ut in the claims.

In the accornpanying drawing, Figure 1 is a plan view 0f an adjustable pipe threading t001 equipped with 1ny improve1nent. Fig. 2 is a si1nilar view, with the housing omitted, the chaser engaging plate being shown in section. Fig. 3 is an enlarged sectional view on 1ine 3-3 Fig. l. Fig. 4 is a view in perspective 0f the chase1 adjusting plate.

In the drawings I have shown a threuding 13001 having the geneml characteristics 0f the t001 covered by Letters Patent 0f the United States N0. 914,503, issued t0 Im W. Nonnernan 011 March 9, 1909, but Such 11001 is shown n1erely t0 illustrate the applicability 0f 1ny improvement, which latter is not confined t0 any special t-ype 0f threading t001. As pointed out in that patent euch chaser 0f twosecs of chasers is provided with a Ing 1 for taking in separate s10ts on the inner face of a chaser adjusting plate 2 Which is axially rot-atable 0n housing 3. Euch of the s1ots is for1ned with two eccentric portions 4 and 5 und an intermediate concentric portion G, the eccentric portions forming the actuating agencies f0r the re- Speoification of Letters Patent.

Application filed August 28, 1909.

Patented J uly 12, 1910. Serial N0. 515,061.

[ spective sets of chasers, being inclined in opposite directions. The outward pressure 011 the chase1s in threading a pipe tends to constantly tn1n the chaser adjusting plate and cause the chasers to 1nove outwardly. T0 overco1ne this tendency and prevent any accidental rotation 0f the chaser adjusting plate I forn1 that portion 0f the platze With which the locking agency engages Wih an eccentric 01' camlike surface inclined in opposition to the inclination 0f the eccentric ortion of the slot of the chaser adjusting p1ate with the resu1t that the latter is prevented from rotating since the passage of a thickened portion of 1netal beneath the locking agency is impossible.

In the present instance I have shown the 02m1 adjusting p1ate as forrned 0n its periphery with tWo oppositely extended cam surfaces 7 and S; and as the locking ageney I have shown a rod 9 passed through an openin,g in the housing and having a head 10 beveled to engage the c2un surfaces. This rod is shown as provided with a nut 12 by which it may be tightened to l0ck the plate to the housing. In the present instance tw0 can1 surfaces are shown, extend ing in opposite directions, because the eccentric portions 0f the s1ots 0f the chaser adjusting plate are inclined in opposite directions. The inclination of each c2un surface is in direct opposition to the inclina tion of the respective eccentric portion of the cum slots. In consequence when the lock has been tightened to hold either set of chasers in position f01 threading a pipe of a given size, turning of the plate under the outward thrust of the chasers is impossible f01 that any such turning Wou1d cause a thickened portion of the 1netal t0 engage the 1ock.

My invention is not confined to a. pipe threading tool having any special numbe1r 01 chasers, nor is it Confined t0 one wherein a single cam plate controls the positions 0f two sets of chasers. The invention may be employed in connection with any adjustable pipe threading t001 wherein the outward pressure of the nipe against the chasers during the cutting operation tends to turn the chaser adjusting p1ate axially, and according t0 my invention such tu1ning is prevented by forrning that portion 0f the chase1 adjusting plate with Which the lock engages eccentrically t0 the axis of the platze, the

inclination of the eccentric surface being opposite .to the inc]ination 0f the actuating portion of the plate with Which the chasers engage.

I claim as my invention:

1. In a pipe threading t001 having a series 0f radiall y arranged chasers und a rotata'ble c'haser ad]uSt1l1g p1ate hav1ng eccentric portions engaging the Chasers, a lock f0r frictionally holding said chaser adjusting -;plate, said plate having an eccentric surface with which said lock engages, such eccentr'1c surface beia1g inc1ined oppositely t0 the inclination of :the =said eccent-ric chase1 engaging aportions.

2. In a pipe .threading t001 having 'tWO sets 0f radially movable chasers und a rotatable adjusting plate having two series of eccentric engaging portions for said sets of chasers, said eccent-ric engaging portions 20 agency iS designed t0 engage, the inc1ination of euch cum surface being in opposite direction to the inclination 0f one of the eccentric chaser engaging portions.

In testimony whereotf, I have signed this specification in the presence 0f two sub- 39 scribing witnesses.

FREDERICK G. KOEHLER.

\Vitnessesz M. V. BECHTEL, ITHIEL B. TAYLOR. 

